Author Topic: MPG has dropped  (Read 3878 times)

Offline olly1505

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MPG has dropped
« on: 25 April 2015, 10:00 »
Ok so I had a coolant leak which pretty much emptied my coolant in 48hours, during this time my mpg dropped which seemed normal. Had the pipe replaced that was leaking, leak sorted. But mpg is still low ?? Not awful but a significant drop from pre-leak. Any ideas ?

Offline Dalo Harkin

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Re: MPG has dropped
« Reply #1 on: 26 April 2015, 06:59 »
Over how long a time frame are you measuring the drop, and what's it dropped by?
ARZ K03s, Oettinger Side Skirts, R32 front, Carbon stage 2, Forge 007p (yellow spring), Forge Actuator (yellow spring), Pipercross panel filter with DSG parts, N249 and N112 deleted, SAI deleted, Carbon canister deleted, Rear wiper deleted, Long Life turbo back custom exhaust with 200 cell sports cat, VR6/G60 clutch kit, Creation Motorsport TIP, Catch can, 'Wellycooler', K04 charge pipe, S3 ported inlet manifold - looks pretty standard on the outside though :)

Offline olly1505

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Re: MPG has dropped
« Reply #2 on: 26 April 2015, 18:06 »
MPG has probably dropped by 30% I would say over the last few days. Not weather related. Seemed to start at the same time as my leak which I had fixed. Not sure if related to that ? Or completely different problem..

Offline Dalo Harkin

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Re: MPG has dropped
« Reply #3 on: 27 April 2015, 12:41 »
did you replace the temp sender?
ARZ K03s, Oettinger Side Skirts, R32 front, Carbon stage 2, Forge 007p (yellow spring), Forge Actuator (yellow spring), Pipercross panel filter with DSG parts, N249 and N112 deleted, SAI deleted, Carbon canister deleted, Rear wiper deleted, Long Life turbo back custom exhaust with 200 cell sports cat, VR6/G60 clutch kit, Creation Motorsport TIP, Catch can, 'Wellycooler', K04 charge pipe, S3 ported inlet manifold - looks pretty standard on the outside though :)

Offline olly1505

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Re: MPG has dropped
« Reply #4 on: 27 April 2015, 15:23 »
No. Should I ?

Offline olly1505

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Re: MPG has dropped
« Reply #5 on: 28 April 2015, 10:32 »
I am taking it into my VW dealer on Tuesday. Have never used them before. If they cant confidently identify the issue, would it be best for my tell them to change the temp sensor, air/fuel filter first? When I mentioned cleaning the EGR valve/MAF Sensor they said that probably wont do anything and asked if I had been on forums  :grin:

Also getting them to check a hissing sound(air leak) i seem to get in high revs.. Worried will be the Turbo

I have 170k on the clock fyi

Offline Dalo Harkin

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Re: MPG has dropped
« Reply #6 on: 05 May 2015, 13:12 »
if you're taking it to the stealers, then make sure you come back here before getting the work done would be my advice.

I've had a few issues with the stealers in the past myself, mentioning MAFs, here was one of my issues with the stealers.
took my car for mapping and the MAF was dead, it was a brand new one from VW. after speaking with VW about getting a replacement/refund they said that they needed my car for the day to test if the MAF was faulty, said no as the MAF is off the car by this point (nipped to GSF for one because VW didn't have one in stock) when speaking with VW they said that as the car is modified then their MAFs are not covered by any kind of warranty. After they sent it to Germany for testing it was indeed dead and I collected the cheque the following week! what a PITA!

Basically if you have any engine modifications its hard to justify a genuine MAF
ARZ K03s, Oettinger Side Skirts, R32 front, Carbon stage 2, Forge 007p (yellow spring), Forge Actuator (yellow spring), Pipercross panel filter with DSG parts, N249 and N112 deleted, SAI deleted, Carbon canister deleted, Rear wiper deleted, Long Life turbo back custom exhaust with 200 cell sports cat, VR6/G60 clutch kit, Creation Motorsport TIP, Catch can, 'Wellycooler', K04 charge pipe, S3 ported inlet manifold - looks pretty standard on the outside though :)

Offline olly1505

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Re: MPG has dropped
« Reply #7 on: 10 May 2015, 20:34 »
They basically didn't acknowledge the fault because the engine management didn't show any problems. My drive to work is getting 42MPG. It's normally 50-55MPG. Significant sudden drop. Like I said it started when I had a coolant leak(which is now fixed)

Just serviced it & had all filters changed. Still no better :(

Any ideas ? :(

Offline Rhyso

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Re: MPG has dropped
« Reply #8 on: 10 May 2015, 21:01 »
What car are we talking about?

What power diesel engine have you got? Mileage?

Offline olly1505

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Re: MPG has dropped
« Reply #9 on: 10 May 2015, 21:19 »
Golf GT TDI 150 PD. 2003. Mileage 172k